This invention relates to electrical receptacles, such as for use in wall outlet boxes, with ground fault protection.
For background and general description, reference is made to Virani et al. U.S. Pat. No. 4,010,431, Mar. 1, 1977 which describes a ground fault receptacle on which the present invention improves and which is hereby incorporated by reference.
The general purposes of this invention are to achieve greater package density in a ground fault receptacle and to do so by a manner and means that reduces assembly time and cost. More dense packaging is sought so a fully assembled unit can be installed more easily and quickly in an ordinary outlet box but at the same time the cost needs to be minimized and the reliability maximized.
Among the improvements of this invention are to provide an arrangement including load terminals, of one piece construction for each polarity of lines that have a protruding spring finger so that a varistor for protection of the electronics can be inserted easily between the load terminal fingers and pressure contact made therewith. The housing base and front cover cooperate to maintain the varistor in position. In this manner the need for soldering the varistor into the circuit of the receptacle, as has been required heretofore, is avoided.
In another aspect of the invention, a carrier is provided that permits a sensing transformer, grounded neutral transformer, a hybrid electronic circuit, and a trip solenoid to be preassembled as a unit and simply inserted into the receptacle housing with minimal additional electrical connections. The carrier, which may be of molded plastic material, has a sensor carrier element and a solenoid carrier element that snap together and are interlocked in such a way as to present aligned ports for the leads of the hybrid circuit without requiring bending, cutting or other modification of their configuration. This achieves a unitary electronic sensing and operating pre-assembly with high density and economy.